I got the same response from my local Service Center manager. He told me that on Tuesday (April 1, 2014, and I do not believe he was pulling an April Fool's joke on me) a software "patch" was installed in my car OTA that is supposed to solve the center display reboot issue that my OP in this topic describes.
He said that kind of software install does not produce the standard message on the display informing the user that a change is going to be, or has been, made to the car's firmware, and it does not change the firmware version number. My car is still on 5.9 (1.51.88) which is what it was on when I reported the display reboot issue.
In the past two days I have not had the center display reboot problem occur.
So this was news to me, that Tesla can install OTA software "patches" to our cars that do not display a message on the center display before or after installation, do not require us to "accept" the install and do not change the firmware number. Up to this point I had always assumed that any software change sent OTA by Tesla would trigger the message on the screen informing the user about the change.
I am fine with getting a "patch" with no indication of it, I was just surprised to learn that Tesla did that. I suppose some people will find this capability disturbing in some way, that they don't always have "control" over when to accept a software change. But the reality is that these cars are rolling computers that have safety-critical aspects to them, and the manufacturer has to be able to make changes to them that they feel are in the best interest of the customer and to keep the customer safe. If someone doesn't like that they should buy a different car, but I predict that 10 years from now almost all cars are going to function the way the Model S does: continuous software changes over time, some of them new features but many of them "patches" to fix problems, and the user has essentially no choice but to accept the software changes, just like our desktop and mobile computers work right now.